The purpose of this study is to determine whether Omeprazole (Prilosec) can be given down a Nasogastric (NG) tube rather than as a pill. Presently there are recommendations, based on theoretical considerations, that Omeprazole should not be given via an NG tube. However, if no difference in absorption or effect is shown, this form of administration could be of great benefit to patients unable to take a pill who need this medicine (such as Intensive Care Unit patients).